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Re: BCP38 tester?
From: Karl Auer <kauer () biplane com au>
Date: Mon, 01 Apr 2013 19:02:40 +1100

On Mon, 2013-04-01 at 01:31 -0500, Jimmy Hess wrote:
On 3/31/13, Karl Auer <kauer () biplane com au> wrote:
OK - how does one configure NAT so that the source addresses of outbound
packets are NOT clamped to a configured range on the outside of the NAT
device? Given this general scenario, of course:

He said it depends on how NAT is configured
[...]
In some implementations, only certain ranges of source IP addresses
are subject to translation.

Um - if no address translation takes place, then, by definition, NAT has
not taken place.

So it may well be that a particular device, capable of doing NAT and
other things, of NATting some packets but not others, may permit
spoofed-because-not-NATted outbound packets, but I remain unconvinced
that a spoofed packet can make it through a NAT process and head
outbound without getting its source address clamped to a configured
range of outside addresses.

Now I'm imagining a NAT process that translates only *destination*
addresses - hm, is there such a beast?

Continuing to seek enlightenment...

Regards, K.

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Karl Auer (kauer () biplane com au)
http://www.biplane.com.au/kauer
http://twitter.com/kauer389

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